A professor thinks of two consecutive numbers between 1 and 10.
'A' knows the 1st number and 'B' knows the second number

A: I do not know your number.
B: Nor do I know your number.
A: Now I know.

What are the four solutions for this?

Find the 8 in the below-given Image.

What Adam and Eve do not have but the rest of the people have?

I am a type of vehicle that has two wheels and is powered by humans. What am I?
Hint 1: You can ride me for exercise.
Hint 2: I am environment-friendly.

Who is generally closer to the kids, mom or dad?

(it's a funny riddle)

You have four chains. Each chain has three links in it. Although it is difficult to cut the links, you wish to make a single loop with all 12 links. What is the fewest number of cuts you must make to accomplish this task?

With pointed fangs I sit and wait; with piercing force I crunch out fate; grabbing victims, proclaiming might; physically joining with a single bite. What am I?

Find out the missing number in the picture attached:

Look at this sequence from top to bottom. What is the next number in the sequence?
1
11
21
1211
111221
312211

Which is heavier: a ton of bricks or a ton of feathers?